Answer:
12
Step-by-step explanation:
5(x-6)=2(x+3)
multiply
5*x and 5*6. 2*x and 2*3
5x-30=2x+6
minus 5x and 2x
3x-30=6
add 30 to 6
3x=36
divide both sides by 3 and the 3x cancels so 36÷3
x=12
You should add the picture so we can see
Answer:
10
Step-by-step explanation:
abolute value= distance from zero 10 is 10 away from 0
Answer:
Hi,
Step-by-step explanation:
The playground 's area is the difference of 2 squares:
20²-10²=(20+10)*(20-10)=30*10=300 (ft²)
Answer:
Step-by-step explanation:
Hello!
X: the lifespan of a new computer monitor of Glotech.
The average life is μ= 85 months and the variance δ²= 64
And a sample of 122 monitors was taken.
You need to calculate the probability that the sample mean is greater than 86.6 months.
Assuming that the variable has a normal distribution X~N(μ;δ²), then the distribution of the sample mean is X[bar]~N(μ;δ²/n)
To calculate this probability you have to work using the sampling distribution and the following formula Z= (X[bar]-μ)/δ/√n ~N(0;1)
P(X[bar]>86.6)= 1 - P(X[bar]≤86.6)
1 - P(Z≤(86.6-85)/(8/√122))= 1 - P(Z≤2.21)= 1 - 0.98645= 0.013355
The probability of the sample mean is greater than 0.013355
I hope this helps!